Implement new features for svg components + improve form properties (#25)

- Make Dimension an actual svg line
- Implement XPositionReference
- Select the container above after delete
- Remove DimensionLayer
- Improve form properties

Reviewed-on: https://git.siklos-chaneru.duckdns.org/Siklos/svg-layout-designer-react/pulls/25

src/Interfaces/AvailableContainer.ts

@@ -1,9 +1,11 @@
 import React from 'react';
+import { XPositionReference } from '../Enums/XPositionReference';
 
 /** Model of available container used in application configuration */
 export interface AvailableContainer {
   Type: string
   Width: number
   Height: number
+  XPositionReference?: XPositionReference
   Style: React.CSSProperties
 }